function howCir(r,option=1){
	var cir = () => 2*3.14*arguments[0]
	var area = ()=>arguments[0]*arguments[0]*3.14
	switch(option){
		case 1: return cir()
		case 2: return area()
		default:return cir()
	}
}
console.log(howCir(1,2))

